JP2011095547A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin display device capable of displaying a stereoscopic image having excellent visibility. <P>SOLUTION: A cellular phone 1, which is a display device, includes illumination devices 10, 20 for stereoscopic display including: light guide plates 12, 22 installed on the back side of a liquid crystal panel 1108; and light sources 11, 21 for allowing incidence of light into the light guide plates 12, 22 from at least one end face 12b, 22b of the light guide plates 11, 22. The light guide plates 12, 22 have a plurality of structures 112-1 to 112n, 122-1 to 122-n having each different shape mutually, along a surface in parallel with a display surface of the liquid crystal panel 1108. Each of the structures is arranged based on a display position of an element image, and reflects light from the light sources 11, 21 to a direction of the liquid crystal panel 1108. Each light guide plate 12, 22 is arranged on a position having each distance different from each other from the back of the liquid crystal panel 1108. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a display device that displays a stereoscopic image.

  2. Description of the Related Art Conventionally, a stereoscopic image display device that allows a user to visually recognize a stereoscopic image without using dedicated glasses is known. Further, a configuration using a light guide plate is known as the stereoscopic image display device in order to make the luminance of the display panel uniform. Furthermore, as the stereoscopic image display device, a configuration in which an image to be displayed is displayed in a time division manner is also known.

  Patent Document 1 discloses a liquid crystal display device that uses a light guide plate and performs time-division display as the stereoscopic image display device. The liquid crystal display device includes a surface light source.

  The surface light source emits light incident from the incident end surface in the Y-axis direction on the side opposite to the observation side of the liquid crystal display panel in which image data for the left eye and image data for the right eye are selectively written. A light guide plate that emits light to the display panel side is provided. In addition, the surface light source refracts light incident from the first direction inclined to one end side in the X-axis direction in a direction inclined at a predetermined angle to the left and makes it incident on the light guide plate, and enters from the second direction. A prism that refracts the incident light in a direction inclined at a predetermined angle to the right when viewed from the liquid crystal display panel side with respect to the Y-axis and enters the light guide plate. Further, the surface light source includes first and second solid state light emitting elements that emit light from the first direction and the second direction toward the prism. The surface light source emits light from the first solid state light emitting element as left eye illumination light, and emits light from the second solid state light emitting element as right eye illumination light.

  The liquid crystal display device intends to realize display of a high-resolution stereoscopic image with the above-described configuration.

  Patent Document 2 discloses a stereoscopic image display device that performs time-division display. The stereoscopic image display device includes image display means having a display surface, a lenticular lens, and a light deflection element.

  The image display means has a pixel region corresponding to the lens pitch of the lenticular lens on the display surface. Each pixel area is composed of two pixels. Each pixel displays an image divided from two images by time division. The stereoscopic image display device changes the traveling direction of the light flux by driving the light deflection element in synchronization with the time-division image display. As a result, the image light emitted from one lens should be collected at two viewpoints, but is swung in two directions with time, and can be seen from four viewpoints, and a stereoscopic image can be seen from three observation positions.

JP 2006-184506 A JP 2005-223727 A

  However, the liquid crystal display device disclosed in Patent Document 1 is a device that is adapted only to the twin-lens type and cannot be adapted to the multi-lens type. For this reason, the liquid crystal display device has a narrow viewing zone.

  In the stereoscopic image display device disclosed in Patent Document 2, the image display means, the lenticular lens, and the light deflection element are arranged in this order. Therefore, it is difficult to reduce the thickness of the stereoscopic image display device.

  This invention is made | formed in view of the said problem, Comprising: The objective is to provide the thin display apparatus which can display the stereo image excellent in visibility.

  According to an aspect of the present invention, the display device displays a stereoscopic image on the display panel by displaying a plurality of element images on the display panel. The display device includes a 3D display light guide plate installed on the back side of the display panel, and a 3D display including a light source that causes light to enter the 3D display light guide plate from at least one end surface of the 3D display light guide plate. A lighting device is provided. The 3D display light guide plate has a plurality of structures having different shapes along a plane parallel to the display surface of the display panel. Each of the structures is arranged based on the display position of the element image, and reflects light from the light source toward the display panel. The display device includes a plurality of stereoscopic display illumination devices. The three-dimensional display conductor plates included in the three-dimensional display lighting devices are arranged at different distances from the back surface of the display panel.

  Preferably, the display device further includes light source control means for controlling light emission timing of each light source included in each stereoscopic display illumination device, and display control means for displaying an element image on the display panel. A light source control means switches the light source to light-emit among several light sources by a time division. The display control means switches element images in synchronization with switching of the light source that emits light. The plurality of structures are arranged at positions shifted from each other between the light guide plates for stereoscopic display.

  Preferably, the interval of the arrangement of the plurality of structures is constant in a stereoscopic display light guide plate including the plurality of structures, and the interval is different between the stereoscopic display light guide plates. The three-dimensional light guide plates have different element image widths corresponding to the structures.

Preferably, the display device further includes a two-dimensional illumination device.
Preferably, the display panel is a liquid crystal display panel including a plurality of pixels and a black matrix. The positions of the element images displayed by the light emission of the light sources are shifted from each other according to the light source that emits light among the plurality of light sources. When the amount of deviation is D, the width of a pixel in a certain direction is Wp, the width of a black matrix in a certain direction is Wb, and a natural number is n, a relationship of D ≦ Wp × n ± Wb × 2 is established.

  Preferably, the display panel is a liquid crystal display panel including a black matrix. The positions of the element images are shifted from each other between the stereoscopic display illumination devices. The amount of deviation is not more than twice the width of the black matrix.

  A stereoscopic image with excellent visibility can be displayed. Furthermore, the apparatus can be thinned.

It is the figure which showed the external appearance of the mobile phone. It is the figure which showed the hardware constitutions of the mobile telephone. It is a figure for demonstrating 5 eyes knowledge solid display. It is a figure for demonstrating the process which produces | generates a stereo image. It is the figure which showed the specific structure of the mobile telephone. It is a perspective view of a mobile phone. It is a figure for demonstrating the control apparatus contained in a mobile telephone. It is the figure which showed arrangement | positioning of an element image. It is a figure for demonstrating the image based on the parallax image which can be observed with each light-guide plate in an observation area | region. It is a figure for demonstrating the element image by a 1st light-guide plate, and the element image by a 2nd light-guide plate. It is a figure for demonstrating the image by a 1st light-guide plate, and the image by a 2nd light-guide plate. It is the figure which showed the display area of the parallax image when arrange | positioning diagonally of an element image. It is a figure for demonstrating the method to reduce the jump between parallax images when using a 1st light guide plate, a 2nd light guide plate, and a 4th light guide plate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[Embodiment 1]
An embodiment of a display device according to the present invention will be described below with reference to FIGS. In this embodiment, a mobile phone is described as an example of a display device. The display device is not limited to a mobile phone. For example, the display device may be a device having a display function such as a PDA (Personal Digital Assistant), an electronic dictionary, and a television.

<Appearance>
FIG. 1 is a diagram showing an appearance of the mobile phone 1. Referring to FIG. 1, mobile phone 1 includes a microphone 1105, operation keys 1107, a liquid crystal panel 1108, and earphones 1109.

  The mobile phone 1 includes a first housing 1000A and a second housing 1000B. The first housing 1000A and the second housing 1000B are foldably connected by a hinge 1000C. The first housing 1000A includes a liquid crystal panel 1108 and an earphone 1109. Second casing 1000B includes operation keys 1107, a microphone 1105, and a camera (not shown).

  Hereinafter, the short side direction (horizontal direction) of the liquid crystal panel 1108 is also referred to as “X direction”. The longitudinal direction (vertical direction) of the liquid crystal panel 1108 is also referred to as “Y direction”.

<Hardware configuration>
FIG. 2 is a diagram illustrating a hardware configuration of the mobile phone 1. Referring to FIG. 2, mobile phone 1 includes CPU 1100, RAM 1101, ROM 1102, communication unit 1103, camera 1104, microphone 1105, speaker 1106, operation key 1107, liquid crystal panel 1108, and earphone 1109. Including. Each component is connected to each other by a data bus DB1.

  The CPU 1100 executes a program. The operation key 1107 receives an instruction input from the user of the mobile phone 1. The RAM 1101 stores data generated by executing a program by the CPU 1100 or data input via the operation keys 1107. The ROM 1102 stores data in a nonvolatile manner. The ROM 1102 is a ROM capable of writing and erasing, such as an EPROM (Erasable Programmable Read-Only Memory) and a flash memory. The communication unit 1103 performs wireless communication with other electronic devices (not shown).

  The camera 1104 captures a subject in accordance with the operation of the operation key by the user. The image data of the photographed subject is stored in the RAM 1102 or an external memory (for example, a memory card).

  The microphone 1105 receives user's voice input. The cellular phone 1 digitizes the input voice (analog data). Then, the mobile phone 1 sends the digitized voice to a communication partner (for example, another mobile phone).

  The speaker 1106 outputs sound based on, for example, music data stored in the RAM 1101. Earphone 1109 outputs the voice sent from the communication partner.

  The liquid crystal panel 1108 displays an image stored in the ROM 1102 or the RAM 1101. The liquid crystal panel 1108 displays, for example, an image taken by the camera 1104.

  Note that the mobile phone 1 may be configured to include a display panel (for example, an organic EL) other than the liquid crystal panel instead of the liquid crystal panel 1108. Alternatively, the mobile phone 1 may be configured to include a photosensor liquid crystal panel instead of the liquid crystal panel 1108.

  By the way, the processing in the mobile phone 1 is realized by each hardware and software executed by the CPU 1100. Such software may be stored in the ROM 1102 in advance. The software may be stored in a storage medium and distributed as a program product. Alternatively, the software may be provided as a program product that can be downloaded by an information provider connected to the so-called Internet. Such software is read from the storage medium or downloaded via the communication unit 1103 or the communication IF (not shown), and then temporarily stored in the ROM 1102. The software is read from the ROM 102 by the CPU 100 and stored in the RAM 101 in the form of an executable program. CPU 1100 executes the program. Since the hardware operation of mobile phone 1 is well known, detailed description will not be repeated.

The storage medium is not limited to a memory card, but is a CD-ROM, FD (Flexible Disk), hard disk, magnetic tape, cassette tape, optical disk (MO (Magnetic Optical Disc) / MD (Mini Disc) / DVD (Digital Versatile). Disc)), IC (Integrated Circuit) cards (excluding memory cards), optical cards, mask ROM, EPROM, EEPROM (Electronically Erasable Programmable Read-Only Memory), flash ROM, and other semiconductor memories, etc. It may be a medium to be used.

  The program here includes not only a program directly executable by the CPU but also a program in a source program format, a compressed program, an encrypted program, and the like.

<Overview of operation>
Hereinafter, as an example of multi-view stereoscopic display, a case where the mobile phone 1 performs 5-view stereoscopic display will be described as an example. Note that the mobile phone 1 is not limited to a five-eye device.

  In order to create a five-eye stereoscopic display image, images viewed from the same direction as the parallax are used for the number of parallaxes (that is, for five parallaxes). Here, “an image viewed from the same direction as the parallax” is an image of the object viewed from five different directions, and “the same direction as the parallax” is a direction that satisfies the parallax generated when the object is observed. .

  FIG. 3 is a diagram for explaining the five-eye stereoscopic display. Referring to FIG. 3, the “image viewed from the same direction as the parallax” is more specifically an image when the observer views the target object from five different observation positions determined in advance. Of the five observation positions OP1 to OP5, when the positions of the observer's eyes 910 and 920 are at the observation position OP1 and the observation position OP3, respectively, the same direction as when the object is viewed from the observation positions OP1 and OP3. By viewing the parallax images taken from the above with the respective eyes 910 and 920, stereoscopic vision becomes possible.

  In the following, the first parallax image, the second parallax image, the third parallax image, the fourth parallax image, and the fifth parallax image are respectively referred to as “parallax image I1” and “parallax image”. These are referred to as “I2”, “parallax image I3”, “parallax image I4”, and “parallax image I5”.

  The mobile phone 1 generates a stereoscopic image using five images from the parallax images I1 to I5 for five-eye stereoscopic display. For example, in the mobile phone 1, the first pixel column of the stereoscopic image is the first pixel column of the parallax image I1, the second column is the second pixel column of the parallax image I2, and the third column is the parallax image. The third pixel row of I3, the fourth row is the fourth pixel row of the parallax image I4, the fifth row is the fifth pixel row of the parallax image I5, and so forth, and the five parallax images I1 to I5 Are repeatedly arranged in the order of parallax. The cellular phone 1 generates one stereoscopic image by the arrangement.

  FIG. 4 is a diagram for explaining processing for generating a stereoscopic image. Referring to FIG. 4, the mobile phone 1 generates stereoscopic images J1 and J2 using five parallax images I1 to I5. The parallax image I1 includes unit images I1a to I1h. Moreover, the parallax image I2, the parallax image I3, the parallax image I4, and the parallax image I5 include unit images I2a to I2h, unit images I3a to I3h, unit images I4a to I4h, and unit images I5a to I5h, respectively. For simplicity of explanation, the number of unit images is eight, but the number of unit images is not limited to eight.

  The mobile phone 1 includes a unit image I1a of the parallax image I1, a unit image I2b of the parallax image I2, a unit image I3c of the parallax image I3, a unit image I4d of the parallax image I4, a unit image I5e of the parallax image I5, The stereoscopic image J1 is generated by arranging the unit image I1f of the parallax image I1, the unit image I2g of the parallax image I2, and the unit image I3h of the parallax image I3 in this order.

  Furthermore, the mobile phone 1 includes a unit image I4a of the parallax image I4, a unit image I5b of the parallax image I5, a unit image I1c of the parallax image I1, a unit image I2d of the parallax image I2, and a unit image I3e of the parallax image I3. Then, the unit image I4f of the parallax image I4, the unit image I5g of the parallax image I5, and the unit image I1h of the parallax image I1 are arranged in this order to generate the stereoscopic image J2.

  The mobile phone 1 displays the stereoscopic image J2 after displaying the stereoscopic image J1. That is, the mobile phone 1 performs time division display. A user (hereinafter also referred to as an “observer”) visually recognizes an image of I1c of the stereoscopic image J2 at a certain observation position, for example, following the unit image I1a of the stereoscopic image J1, with a specific configuration of the mobile phone 1 described later. It will be.

  In the conventional multi-view display device, since the parallax image that can be seen by the observer is an image that is thinned by the number of parallaxes, the resolution of the parallax image is “1 / parallax number”. That is, in the case of the conventional five-eye display device, the resolution of the parallax image is “1/5”.

  However, in the mobile phone 1, as described above, the user can visually recognize the I1c image of the stereoscopic image J2 following the unit image I1a of the stereoscopic image J1 at a certain observation position. For this reason, the resolution of the parallax image of the mobile phone 1 is twice that of the conventional device.

  Thus, the mobile phone 1 can display a stereoscopic image having excellent visibility. In addition, since the mobile phone 1 is a five-lens type, the viewing area is wider than that of a two-lens display device.

<Specific configuration of device>
FIG. 5 is a diagram showing a specific configuration of the mobile phone 1. FIG. 5 is also a sectional view showing a section of the mobile phone 1. Referring to FIG. 5, mobile phone 1 includes stereoscopic illumination device 10, stereoscopic illumination device 20, two-dimensional illumination device 30, liquid crystal panel 1108, and control device 70 (not shown). ing. The mobile phone 1 displays a stereoscopic image on the liquid crystal panel 1108 by displaying a plurality of element images on the liquid crystal panel 1108. Details of the element image will be described later.

  The three-dimensional illumination device 10 is a backlight unit. The three-dimensional illumination device 10 includes a first light source 11 and a first light guide plate 12.

  The first light guide plate 12 is installed on the back side of the liquid crystal panel 1108. The first light guide plate 12 includes a plurality of structures 112-1 to 112-n having a plurality of structures different from each other along a plane parallel to the display surface of the liquid crystal panel 1108. Hereinafter, when “structural body 112” is described, it refers to any one of the plurality of structural bodies 112-1 to 112-n.

  The first light source 11 is disposed in the vicinity of the end surface 12 a of the first light guide plate 12. The first light source 11 causes light to enter the first light guide plate 12 from at least one end surface 12 a of the first light guide plate 12. The first light source 11 is, for example, an LED (Light Emitting Diode).

  Each of the structures 112-1 to 112-n is arranged based on a display position of an element image described later. Each of the structures 112-1 to 112-n reflects light from the first light source 11 in the direction of the liquid crystal panel 1108.

  The three-dimensional illumination device 20 is a backlight unit. The three-dimensional illumination device 20 includes a second light source 21 and a second light guide plate 22.

  The second light guide plate 22 is installed on the back side of the first light guide plate 12. Specifically, the liquid crystal panel 1108, the first light guide plate 12, and the second light guide plate 22 are arranged in the mobile phone 1 in this order. The second light guide plate 22 includes a plurality of structures 122-1 to 122-n having different shapes from each other along a plane parallel to the display surface of the liquid crystal panel 1108. In the following, when “structural body 122” is described, any one of the plurality of structural bodies 122-1 to 122-n is indicated.

  The second light source 21 is disposed in the vicinity of the end surface 22 a of the second light guide plate 22. The second light source 21 causes light to enter the second light guide plate 22 from at least one end surface 22 a of the second light guide plate 22. The second light source 21 is, for example, an LED (Light Emitting Diode).

  Each of the structures 122-1 to 122-n is arranged based on a display position of an element image described later. Each of the structures 122-1 to 122-n reflects the light from the second light source 11 in the direction of the liquid crystal panel 1108.

  As described above, in the mobile phone 1, the conductor plates 12 and 22 included in the stereoscopic display illumination devices 10 and 20 are arranged at positions that are different from each other from the back surface of the liquid crystal panel 1108.

  In addition, the plurality of structures 112-1 to 112-n in the first light guide plate 12 and the plurality of structures 122-1 to 122-n in the second light guide plate 22 are the light guide plates 12 and 22, and each other. It is arranged at a shifted position.

  The intervals PS1 and PS2 of the arrangement of the plurality of structures are constant in the light guide plates 12 and 22 including the plurality of structures. That is, in the 1st light guide plate 12 and the 2nd light guide plate 22, the space | interval (pitch) between structures is respectively constant. Further, the intervals PS1 and PS2 are different from each other between the light guide plates 12 and 22. That is, the interval PS1 and the interval PS2 are different.

  Furthermore, although mentioned later in detail, the width | variety of the element image corresponding to a structure differs mutually between the 1st light guide plate 12 and the 2nd light guide plates 22. FIG.

  The two-dimensional illumination device 30 is a backlight unit. The two-dimensional illumination device 30 includes a third light source 31 and a third light guide plate 32. The light emitted by the third light source 31 enters the third light guide plate 32 from the end surface 32a, and the incident light exits from the surface 32b. The third light source 31 is, for example, an LED (Light Emitting Diode). In addition, since the 3rd light guide plate 32 is a general light guide plate, the detailed description about the 3rd light guide plate 32 is not performed.

  The mobile phone 1 can perform two-dimensional display at the resolution of the liquid crystal panel 1108 by using the two-dimensional illumination device 30. The mobile phone 1 can switch from the two-dimensional display to the three-dimensional display by switching the light irradiation from the two-dimensional illumination device 30 to the three-dimensional illumination devices 10 and 20.

  FIG. 6 is a perspective view of the mobile phone 1. With reference to FIG. 6, the observer 900 visually recognizes the display surface of the liquid crystal panel 1108 from the observation positions OP1 to OP5 of the observation region M1. Here, each observation position is an area having a predetermined width. Specifically, each observation position is an area having a width obtained by dividing the width of the observation area M1 by the number of parallaxes (hereinafter also referred to as “parallax area”). As described above, in the mobile phone 1, the liquid crystal panel 1108, the first light guide plate 12, the second light guide plate 22, and the third light guide plate 32 are arranged in this order.

  Hereinafter, a more specific configuration of the mobile phone 1 will be described with reference to FIG. 5 again. In the mobile phone 1, the position of the observation area M <b> 1 is a position where the distance Z from the display surface of the liquid crystal panel 1108 is 600 mm. The width W of the observation area M1 is 160 mm. Since the mobile phone 1 is a five-eye device, the number of parallaxes is five parallaxes. Further, the width of the parallax region is 32 mm. Hereinafter, the distance Z is also referred to as “viewing distance Z”.

  The liquid crystal panel 1108 is a transmissive liquid crystal panel. In the liquid crystal panel 1108, one pixel is composed of three pixels of an R pixel, a G pixel, and a B pixel. The picture element is a square picture element having a side of 0.3 mm. Each pixel has a rectangular shape with a vertical width H = 0.3 mm and a horizontal width W = 0.1 mm. Each pixel has a black matrix region.

  In the liquid crystal panel 1108, the area of the black matrix is 0.04 mm above and below each pixel and 0.04 mm left and right. The mobile phone 1 displays a picture with different parallax for each pixel. In the mobile phone 1, the number of parallaxes is 5 parallaxes, so a 1-element image 81 is formed with 5 pixels. Since a single element image is composed of five pixels, the “unit image” shown in FIG. 4 and the like is one pixel. Hereinafter, the unit image is also referred to as “pixel”.

(Regarding the structure of the first light guide plate 12)
Each structure 112-1 to 112-n is a linear structure. More specifically, each of the structures 112-1 to 112-n is a triangular prism. In the first light guide plate 12, the surface 12b on the liquid crystal panel 1108 side is a light emission surface. Hereinafter, the surface 12b is referred to as an “emission surface 12b”. Each of the structural bodies 112-1 to 112-n is arranged on the surface of the first light guide plate 12 on the side opposite to the emission surface 12 b with a number corresponding to the number of element images at equal intervals.

  The distance h1 between the back surface of the liquid crystal panel 1108 and the bottom surface of the first light guide plate 12 (that is, the surface on the opposite side) is the element image 81 pitch PE, the width W of the observation region M1, and the display surface of the liquid crystal panel 1108. Is represented by the following formula (1) based on the distance Z of the observation region M1 from:

h1 = PE × Z / (W-PE) = 1.88 mm (1)
Further, the pitch PS <b> 1 of the structures 112-1 to 112-n included in the first light guide plate 12 is determined based on the position of the element image in the liquid crystal panel 1108. Based on the pitch PE of the element image 81, the distance h1, and the distance Z, the following expression (2) is given.

PS1 = PE × (Z + h1) /Z=0.50 mm (2)
According to Expression (2), it can be seen that the cellular phone 1 has a relationship of PS1> PE.

  The structures 112-1 to 112-n of the first light guide plate 12 are continuously arranged in parallel with the arrangement direction of the element images 81 at the pitch PS <b> 1 calculated from the above equation (2).

(Regarding the structure of the second light guide plate 22)
Each structural body 122-1 to 122-n is a linear structure body, like each structural body 112-1 to 112-n of the first light guide plate 12. More specifically, each of the structures 122-1 to 122-n is a triangular prism. In the second light guide plate 22, the surface 22b on the liquid crystal panel 1108 side is a light emission surface. Hereinafter, the surface 22b is referred to as an “emission surface 22b”. The respective structures 122-1 to 122-n are arranged on the surface of the second light guide plate 22 on the side opposite to the emission surface 22b at equal intervals with the number corresponding to the number of element images.

(About the trajectory of light)
The trajectory of light emitted by the first light source 11 will be described. When light from the first light source 11 enters from the end face 12a of the first light guide plate 12, the incident light (hereinafter referred to as “incident light”) travels in the traveling direction while being totally reflected in the first light guide plate 12. Proceed to

  When incident light is reflected or scattered by the structures 112-1 to 112-n, the incident light is emitted from the emission surface 12 b of the first light guide plate 12. The light emitted from the emission surface 12b irradiates the element image 81 corresponding to the structure 112 on a one-to-one basis.

  In this case, the incident light can be spread over the entire surface of the first light guide plate 12 by gradually increasing the size of the structure 12 in the first light guide plate 12 away from the first light source 11 while maintaining a similar shape. it can. As a result, each of the structures 112-1 to 112-n can secure a reflecting surface for uniform reflection.

  The reflected light from the reflecting surface of the structure 12 at this time irradiates the corresponding element image 81, and projects an image with uniform brightness within a predetermined observation area. At this time, the structure 12 can be regarded as one linear light source.

  In FIG. 1, only the element image 81 corresponding to the reflected light from the structure 12 in a one-to-one correspondence is illustrated. However, other element images 81 are actually irradiated. . However, the irradiation light to the element image 81 that does not correspond to the projection of the image outside the predetermined observation area does not affect the stereoscopic view in the observation area.

<Configuration of Control Device 70>
FIG. 7 is a diagram for explaining the control device 70 included in the mobile phone 1. With reference to FIG. 7, the control device 70 includes a display control unit 71 and a light source control unit 72.

  The light source control unit 72 controls the light emission timings of the light sources 11 and 21 included in the stereoscopic display illumination devices 10 and 20. The light source control unit 72 switches the light source to emit light among the plurality of light sources 11 and 21 in a time division manner.

  The display control unit 71 displays the element image 81 on the liquid crystal panel 1108. More specifically, the display control unit 71 switches element images in synchronization with switching of the light sources 11 and 21 that emit light. That is, the display control unit 71 switches the stereoscopic images J1 and J2 in synchronization with the switching of the light sources 11 and 21 that emit light, as shown in FIG. For example, the display control unit 71 displays the stereoscopic image J1 when the first light source 11 emits light, and displays the stereoscopic image J2 when the second light source 21 emits light.

<Arrangement of element images>
FIG. 8 is a diagram showing the arrangement of element images. FIG. 8A is a diagram showing an element image 81 when the first light source 11 emits light. FIG. 8B is a diagram showing an element image 82 when the second light source 21 emits light.

  Referring to FIG. 8A, the element image 81 includes five unit images. Referring to FIG. 8B, the element image 82 is also composed of five unit images, like the element image 81. Since the positions of the structure body 112 and the structure body 122 corresponding to the structure body 112 are shifted (see FIG. 5), in the mobile phone 1, the element image 82 is arranged so as to be shifted from the element image 81 by about two pixels. Become. The shift amount of the element image is determined according to the shift amount of the positions of the structures 112 and 122.

  The first light guide plate 12 and the second light guide plate 22 irradiate parallax images corresponding to the regions OP1 to OP5 in the observation region M1, respectively. The observer 900 can stereoscopically view. Further, as described above, when the third light source 31 in the two-dimensional illumination device 30 is caused to emit light, the mobile phone 1 can perform two-dimensional display with the resolution of the liquid crystal panel 1108.

  Regarding the first light guide plate 12, for example, five pixels I1a to I5e included in one element image 81 are sequentially projected onto the observation positions OP1, OP2, OP3, OP4, and OP5 in the observation region M1, respectively. . Regarding the second light guide plate 22, the five pixels I1a to I5e included in the element image 81 are sequentially projected onto the observation positions OP4, OP5, OP1, OP2, and OP35 in the observation region M1. That is, the first light guide plate 12 and the second light guide plate 22 are projected with the five pixels I1a to I5e shifted. Therefore, the five pixels I1c, I2d, I3e, I4f, and I5g shifted by two pixels from the element image 81 of the first light guide plate 12 become the element image 82 of the second light guide plate 22.

  As described above, since the element images 81 and 82 are shifted by about 2 pixels between the first light guide plate 12 and the second light guide plate 22, a stereoscopic image for each light guide plate 12 and 22 (see FIG. 4) by the method described above. When the reference) is created, the pixel columns to be synthesized with the respective parallax images are also shifted by about two pixels. For example, in the case of the parallax image I1, the first light guide plate 12 displays an image of a pixel row skipping five pixels such as the first row, the sixth row, the eleventh row,. A pixel row skipped by 5 pixels such as the third row, the eighth row, the thirteenth row, and so on is displayed.

  FIG. 9 is a diagram for explaining an image based on the parallax image I1 that can be observed by the light guide plates 12 and 22 in the observation region M1 described above. The parallax image I1α is a first parallax image that can be observed by the observer 900 when the first light source 11 emits light and light is emitted from the first light guide plate 12. The parallax image I1β is a first parallax image that can be observed by the observer 900 when the second light source 21 emits light and the second light guide plate 22 emits light.

  The parallax image I1γ is a first parallax image that can be observed when the first light source 11 and the second light source 21 emit light in a time-sharing manner and the image on the liquid crystal panel 1108 is switched in synchronization with the light emission. In synchronization with the switching timing of light emission between the first light source 11 and the second light source 21, when the image displayed on the liquid crystal panel 1108 is switched and the image is displayed in a time division manner, if the switching speed is set to about 120 fps, observation is performed. The person 900 is in the same state as watching two images (parallax images I1α and I1β) at the same time.

  Specifically, when light is irradiated from the first light guide plate 12, a parallax image I1α by pixels such as the first column, the sixth column, the eleventh column,... Of the parallax image I1 is projected onto the observation position OP1. On the other hand, when light is irradiated from the second light guide plate 22, a parallax image I1β by pixels such as the third, eighth, thirteenth, and so on of the parallax image I1 is projected onto the observation position OP1.

  By switching the light guide plate to be used and displaying two stereoscopic images (see FIG. 4) projected onto the observation position OP1 in synchronism with the switching, the respective parallax images I1 to I5 are displayed in a conventional manner. In the method, the amount of thinned images can be reduced by the number of light guide plates. That is, the observer 900 sees the parallax image I1γ. As a result, the resolution that was previously “1/5” in the five-eye stereoscopic display can be improved to “2/5” in the mobile phone 1.

  The mobile phone 1 includes a plurality of light guide plates 12, 22, and 32, but does not include a lenticular lens and a light deflection element, and thus can be made thinner than a configuration including the lens or element. .

<Width of element image>
By the way, in the mobile phone 1 in which the structures 112 and 122 of the first light guide plate 12 and the second light guide plate 22 are regarded as linear light sources, the first light guide plate 12 and the second light guide plate 22 are as shown in FIG. The liquid crystal panel 1108 is arranged so as to overlap in parallel with the display surface. Therefore, the structure 122 of the second light guide plate 22 is disposed at a position farther from the liquid crystal panel 1108 than the structure 112 of the first light guide plate 12. For this reason, the range of the panel (the width of the element image) irradiated by each of the structures 112 and 122 is not the same in the first light guide plate 12 and the second light guide plate 22.

  For example, if the configuration of the structure 122 of the second light guide plate 12 is changed so that the size of the element image by the first light guide plate 12 and the size of the element image by the second light guide plate 22 are the same, the observation region In M1, the region where the element image 82 (see FIG. 8B) can be observed becomes narrow. That is, for example, the element image 82 cannot always be observed in the entire region of the observation position OP1.

  In the mobile phone 1, the width of the element image by the second light guide plate 22 is larger than the width of the element image 81 by the first light guide plate 12. For example, if the first light guide plate 12 and the second light guide plate 22 are too far apart, the width of the element image 82 becomes larger than the width of 5 pixels. In this case, a deviation occurs in the image projected on the observation area M1. That is, different parallax images are projected on the respective observation positions OP1 to OP2 in the observation region M1. As a result, crosstalk occurs. Note that “crosstalk” is a phenomenon in which a parallax image at an observation position adjacent to the observation position can be seen at the observation position of the observation region M1.

  Moreover, since the 1st light guide plate 12 and the 2nd light guide plate 22 are piled up, the thickness of each light guide plate 12 and 22 must also be considered, and the 1st light guide plate 12 and the 2nd light guide plate 22 are brought close. There is a limit to the distance that can be achieved.

  FIG. 10 is a diagram for explaining an element image by the first light guide plate 12 and an element image by the second light guide plate 22. With reference to FIG. 10, the element image 81 is displayed by the structure 112-k of the first light guide plate 12. The element image 82A is displayed by the structure 122-k of the second light guide plate 22 corresponding to the structure 122-k. Note that k is a natural number between 1 and n.

  In the actual mobile phone 1, the element image 81 and the element image 82 are shifted by two pixels as described above. In FIG. 10, for convenience of explanation, an element image 82 </ b> A with no deviation is shown instead of the element image 82.

  For this reason, the mobile phone 1 sets the light irradiation range by the first light guide plate 12 to a range not including the black matrix 181 of the pixels 180 at both ends in the element image 81. In addition, the light irradiation range by the second light guide plate 22 is added to the light irradiation range by the first light guide plate 12, and the black matrix 181 of the pixels 180 at both ends in the element image 81 and the adjacent black matrix 181. The range includes the black matrix.

  As described above, the number of parallaxes is 5, the viewing distance is 600 mm, the width W of the observation region M1 is 160 mm, the width of the parallax region is 32 mm, the pixel pitch is 0.0575 mm, and the black matrix width between pixels is 0.021 mm. , The distance h1 between the first light guide plate 12 and the liquid crystal panel 1108 is 1.73 mm, and the distance between the second light guide plate 22 and the liquid crystal panel 1108 (that is, h1 + h2) is 2.03 mm. For this reason, the distance h2 between the first light guide plate 12 and the second light guide plate 22 is 0.30 mm. For this reason, the 1st light guide plate 12 can be made into thickness sufficient in order to fulfill | perform the function as a light guide plate.

  FIG. 11 is a diagram for explaining an image J11 by the first light guide plate 12 and an image J12 by the second light guide plate 22. Referring to FIG. 11, the deviation between image J11 and image J12 can be accommodated in a region where black matrix 181 in observation region M1 is projected. Note that the region 802 is a region corresponding to the black matrix 181. An area 801 is an area corresponding to the color filter.

  In the mobile phone 1, the parallax image displayed by the color filter of the pixel 180 is not observed in a region where another parallax image is projected by the black matrix 181. For this reason, the mobile phone 1 can suppress the occurrence of crosstalk.

  At this time, the pitches PS1 and PS2 of the structures 112 and 122 of the light guide plates 12 and 22 are pitches corresponding to the element images 81 and 82, respectively. The pitch PS1 of the structures 112 in the first light guide plate 12 is obtained by the above-described formula (2). Moreover, since the structure 122 in the second light guide plate 22 has the first light guide plate 12 on the emission surface 22b side, the element image 82 corresponding to the structure 122 is irradiated while considering the influence of the first light guide plate 12. It is necessary to arrange at the position to do.

  In this embodiment, a parallax image in one element image is created in units of one pixel, but may be created in units of two pixels or pixel units. In addition, the arrangement of the element images is arranged in a line in the column direction in the matrix-like pixel arrangement, but the arrangement of the element images may be an irregular arrangement such as arranging the element images obliquely (see FIG. 12). Good.

  In the present embodiment, the amount of shift of the element image by the first light guide plate 12 and the second light guide plate is 2 pixels, but is not limited to 2 pixels. The deviation amount can be set to an arbitrary value as long as no crosstalk occurs. That is, assuming that the amount of deviation is D, the width of the pixel is Wp, the width of the black matrix is Wb, and the natural number is n, the amount of deviation only needs to satisfy the following expression (3).

D ≦ Wp × n ± Wb × 2 (3)
[Embodiment 2]
Another embodiment of the display device according to the present invention is described below with reference to FIGS. In this embodiment, as in Embodiment 1, a mobile phone will be described as an example of a display device. Note that the display device is not limited to the mobile phone as in the first embodiment.

  The display device according to the present embodiment (hereinafter referred to as “mobile phone 1A”) is different from the mobile phone 1 of the first embodiment in that it does not control the light emission timings of the first light source 11 and the second light source 21. Is different. The mobile phone 1A is different from the mobile phone 1 of Embodiment 1 in that the element image is not switched in synchronization with switching of the light source that emits light. The mobile phone 1A is different from the mobile phone 1 of Embodiment 1 in that the element images displayed by the respective light guide plates are not shifted from each other.

  The mobile phone 1A includes a stereoscopic illumination device 10, a stereoscopic illumination device 20, a two-dimensional illumination device 30, a liquid crystal panel 1108, a control device 70, and a stereoscopic illumination device 40 (see FIG. 13). ing. The three-dimensional illumination device 40 is a backlight unit. The three-dimensional illumination device 40 includes a fourth light source 41 and a fourth light guide plate 42 (see FIG. 13). Similar to the first light guide plate 12 and the second light guide plate 22, the fourth light guide plate 42 includes a plurality of structures.

  In the mobile phone 1A, a plurality of structures are provided in each of the light guide plates 12 and 22 so that the element image by the first light guide plate 12 and the element image by the second light guide plate 22 are not shifted by two pixels as described above. Is arranged.

  By the way, in a display device that displays a stereoscopic image, it is possible to alleviate the difference in resolution between the vertical and horizontal directions by slanting the arrangement of the element images, and to reduce the jump between parallax images due to the black matrix. Widely known. In the mobile phone 1A according to the present embodiment, the arrangement of element images is oblique.

  However, when the element images are arranged obliquely, crosstalk is one of the problems when observing a stereoscopic image. As a method for solving the crosstalk, increasing the light distribution of light, increasing the black matrix area, and the like can be mentioned.

  FIG. 12 is a diagram illustrating a display area of a parallax image when the element image is arranged obliquely. Referring to FIG. 12, the display area M2 of the second parallax image I2 includes a pixel 180 of another adjacent parallax image display area.

  This area is a potential crosstalk area M21. In order to improve crosstalk, it is necessary to remove the region M21. For example, as one of improvement measures, it is conceivable to enlarge the area of the black matrix 181 and cover the potential crosstalk area M21 with the black matrix. However, problems when the area of the black matrix is increased as described above include a flipping between parallax images due to the black matrix 181 and a decrease in the amount of light. The cellular phone 1A is configured to be able to solve the problem. Hereinafter, a specific configuration for solving the problem will be described.

  FIG. 13 is a diagram for explaining a method of reducing a jump between parallax images when the first light guide plate 12, the second light guide plate 22, and the fourth light guide plate 42 are used. FIG. 13A is a cross-sectional view of the mobile phone 1A. In FIG. 13A, for convenience of explanation, three liquid crystal panels 1108 are shown, but actually, there is only one liquid crystal panel 1108. FIG. 13B is a diagram for explaining an image visually recognized by the observer 900 in the mobile phone 1A.

  With reference to Fig.13 (a), 1 A of mobile telephones have arrange | positioned the 1st light-guide plate 12, the 2nd light-guide plate 22, and the 4th light-guide plate 42 in this order. Referring to FIG. 13B, in the mobile phone 1A, the observation region M1-A by the first light guide plate 12, the observation region M1-B by the second light guide plate 22, and the observation region M1 by the fourth light guide plate 42 are referred to. The light guide plates 12, 22, and 42 are arranged so that −C is not more than twice the width of the black matrix and deviates in the X direction. For this reason, the image J112 by the first light guide plate 12, the image J122 by the second light guide plate 22, and the image 142 by the third light guide plate 42 are shifted in the X direction by less than twice the width of the black matrix. In this case, the ratio of the color filter to the black matrix in the X direction of the pixel is 2: 1.

  Note that the width of the black matrix is the width of one black matrix 181 located at one end of the pixel 180 (see FIG. 12). Twice the width of the black matrix is the width between adjacent color filters.

  Therefore, even when the black matrix region of the pixel is enlarged to reduce crosstalk, the mobile phone 1A irradiates the region where the black matrix is irradiated with the same parallax image by another light guide plate for stereoscopic display. For this reason, the observer 900 can see the image J100 in which the jump between parallax images is reduced.

  In the present embodiment, the light guide plates 12, 22, and 42 for stereoscopic display are overlapped with each other. However, it is not limited to such a configuration. For example, the mobile phone 1A may be configured to include only one light guide plate for three-dimensional display and to arrange a plurality of structural body rows (for example, three rows) having different pitches in the one light guide plate. Further, if the cellular phone 1A takes the arrangement, the irradiation area can be made the same size, so that an image with higher image quality than that of the configuration not taking the arrangement can be displayed, and further reduction in thickness can be achieved.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Mobile phone, 1A mobile phone, 10 Solid illumination device, 11 1st light source, 12 1st light guide plate, 12a end surface, 20 3D illumination device, 21 2nd light source, 22 2nd light guide plate, 22a end surface, 30 2 Dimensional illumination device, 31 3rd light source, 32 3rd light guide plate, 32a end surface, 40 stereoscopic illumination device, 41 4th light source, 42 4th light guide plate, 70 control device, 71 display control part, 72 light source control part, 81 element image, 82 element image, 82A element image, 112 structure, 122 structure, 180 pixels, 181 black matrix, 1108 liquid crystal panel.

Claims (6)

A display device that displays a stereoscopic image on the display panel by displaying a plurality of element images on the display panel,
A stereoscopic display illumination device comprising: a stereoscopic display light guide plate installed on the back side of the display panel; and a light source for allowing light to enter the stereoscopic display light guide plate from at least one end surface of the stereoscopic display light guide plate. With
The three-dimensional display light guide plate has a plurality of structures having different shapes along a plane parallel to the display surface of the display panel,
Each of the structures is arranged based on a display position of the element image, reflects light from the light source toward the display panel,
The display device includes a plurality of the stereoscopic display illumination devices,
Each of the three-dimensional display conductor plates included in each of the three-dimensional display illumination devices is a display device that is disposed at a different distance from the back surface of the display panel. The display device
Light source control means for controlling the light emission timing of each of the light sources included in each of the stereoscopic display illumination devices;
Display control means for displaying the element image on the display panel;
The light source control means switches light sources that emit light among the plurality of light sources in a time-sharing manner,
The display control means switches the element image in synchronization with switching of the light source that emits light,
The display device according to claim 1, wherein the plurality of structures are arranged at positions shifted from each other between the light guide plates for stereoscopic display. The interval of the arrangement of the plurality of structures is constant in the light guide plate for stereoscopic display including the plurality of structures, and the interval is different from each other for the light guide plates for stereoscopic display,
The display device according to claim 2, wherein the three-dimensional light guide plates have different widths of the element images corresponding to the structures.   The display device according to claim 3, further comprising a two-dimensional illumination device. The display panel is a liquid crystal display panel including a plurality of pixels and a black matrix,
The position of the element image displayed by the light emission of the light source is shifted from each other according to the light source that emits light among the plurality of light sources,
When the amount of deviation is D, the width of the pixel in a certain direction is Wp, the width of the black matrix in the certain direction is Wb, and the natural number is n,
D ≦ Wp × n ± Wb × 2
The display device according to claim 4, wherein the relationship is established. The display panel is a liquid crystal display panel including a black matrix,
The positions of the element images are shifted from each other between the stereoscopic display lighting devices,
The display device according to claim 1, wherein an amount of the shift is not more than twice a width of the black matrix.

Images